ASN1_STRING_dup, ASN1_STRING_cmp, ASN1_STRING_set, ASN1_STRING_length,
ASN1_STRING_type, ASN1_STRING_get0_data, ASN1_STRING_data, ASN1_STRING_to_UTF8
- ASN1_STRING utility functions
#include <openssl/asn1.h>
int ASN1_STRING_length(ASN1_STRING *x);
const unsigned char *ASN1_STRING_get0_data(const ASN1_STRING *x);
unsigned char *ASN1_STRING_data(ASN1_STRING *x);
ASN1_STRING *ASN1_STRING_dup(const ASN1_STRING *a);
int ASN1_STRING_cmp(ASN1_STRING *a, ASN1_STRING *b);
int ASN1_STRING_set(ASN1_STRING *str, const void *data, int len);
int ASN1_STRING_type(const ASN1_STRING *x);
int ASN1_STRING_to_UTF8(unsigned char **out, const ASN1_STRING *in);
These functions allow an
ASN1_STRING structure to be manipulated.
ASN1_STRING_length() returns the length of the content of
x.
ASN1_STRING_get0_data() returns an internal pointer to the data of
x. Since this is an internal pointer it should
not be freed or
modified in any way.
ASN1_STRING_data() is similar to
ASN1_STRING_get0_data() except
the returned value is not constant. This function is deprecated: applications
should use
ASN1_STRING_get0_data() instead.
ASN1_STRING_dup() returns a copy of the structure
a.
ASN1_STRING_cmp() compares
a and
b returning 0 if the two
are identical. The string types and content are compared.
ASN1_STRING_set() sets the data of string
str to the buffer
data or length
len. The supplied data is copied. If
len
is -1 then the length is determined by strlen(data).
ASN1_STRING_type() returns the type of
x, using standard constants
such as
V_ASN1_OCTET_STRING.
ASN1_STRING_to_UTF8() converts the string
in to UTF8 format, the
converted data is allocated in a buffer in
*out. The length of
out is returned or a negative error code. The buffer
*out should
be freed using
OPENSSL_free().
Almost all ASN1 types in OpenSSL are represented as an
ASN1_STRING
structure. Other types such as
ASN1_OCTET_STRING are simply typedef'ed
to
ASN1_STRING and the functions call the
ASN1_STRING
equivalents.
ASN1_STRING is also used for some
CHOICE types
which consist entirely of primitive string types such as
DirectoryString and
Time.
These functions should
not be used to examine or modify
ASN1_INTEGER or
ASN1_ENUMERATED types: the relevant
INTEGER or
ENUMERATED utility functions should be used instead.
In general it cannot be assumed that the data returned by
ASN1_STRING_data() is null terminated or does not contain embedded
nulls. The actual format of the data will depend on the actual string type
itself: for example for an IA5String the data will be ASCII, for a BMPString
two bytes per character in big endian format, and for a UTF8String it will be
in UTF8 format.
Similar care should be take to ensure the data is in the correct format when
calling
ASN1_STRING_set().
ASN1_STRING_length() returns the length of the content of
x.
ASN1_STRING_get0_data() and
ASN1_STRING_data() return an internal
pointer to the data of
x.
ASN1_STRING_dup() returns a valid
ASN1_STRING structure or NULL if
an error occurred.
ASN1_STRING_cmp() returns an integer greater than, equal to, or less than
0, according to whether
a is greater than, equal to, or less than
b.
ASN1_STRING_set() returns 1 on success or 0 on error.
ASN1_STRING_type() returns the type of
x.
ASN1_STRING_to_UTF8() returns the number of bytes in output string
out or a negative value if an error occurred.
ERR_get_error(3)
Copyright 2002-2020 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy in the
file LICENSE in the source distribution or at
<
https://www.openssl.org/source/license.html>.